Improved apparatus for superheating steam



N.PETERS, PHOTLITMOGRAPHER. WASHINGTON. D. Cl;

UNITED STAT-Es .PATENT OFFICE.

GEORGE A. STONE, OF ROXBURY, MASSACHUSETTS.

IIVIPROVED APPARATUS FOR S-UPERHEATING STEAM.

Specification forming part of Letters Patent No. 23,958, dated May 10,1859.

. scriptiomtaken in connection with the draw ings, is a full, clear, andexact description thereof.

In the accompanying drawings, Figure l is an end elevation of a boilerwith my apparatus applied thereto, and Fig. 2 is a section through thesame on the line C D of Fig. l.

The nature of my invention consists in combining a steam-jet or itsequivalent for increasing a draft with a superheating apparatus in whichsteam is heated by gaseous products'of construction or flame drawn outof the boiler-connections, furnaces, or flues by a proper pipe, and thenreturned again to the iues or connections, or to the open air,substantially as specified, the lcombination being such as ishereinafter described, for the purposes set forth.

My invention is applicable to all boilers that I know of or are inordinary use, and may be arranged in a variety of ways. I have in thedrawings shown it applied to a marine boiler of the tubular variety; andarranged in a convenient manner.

In the drawings, the lire-boxes or furnaces are shown at d d d, the backconnection at b I), the tubes at c c c, the front connection at d d, thechimney or stack at ff, and the steam chimney or dome at g g, while thesteampipe is represented at 7L 7L. A pipe or liuc, j j, is connectedwith the back connection at if., extends upward, and is branched intoseveral tubes?v l, located inside of the steampipe, and these tubesenter into another pipe or fine, m, which passes into and connects withthe chimney. By means of these flues and tubes there is an opencontinuous passage .from the back connection or chamber near the ire tothe chimney or extension of the front connection farther from the iire,and a portion of t-he heated gases can pass freely through. suchpassage, heating as they flow along the steam contained in a chamber orthe steam-pipe. By this means it will be perceived that the whole of thegaseous products of combustion are not brought into play, as

they usually are, to heat the steam, and, further, that by placing avalve in the iiuejj the amount of gases used for superheating may bein ameasure regulated, or the gases altogether shut off and the steam usedas generated; but it will be perceived that the passage through thesuperheating apparatus is longer than the direct passage through thetubes and connections of the boiler, and also less direct. Thereforethere will never be such a flow of gas through the former as to heat thesteam too much. Regulation, therefore, will be best attained byproviding means to increase at will the iiow of gases through thesuperheating apparatus, and for this purpose I have located inside ofthe flue which connects with that part of the boiler farthest from there a pipe, o, filled with a proper regulating valve or cock--such asp-and connected at one end with the steam-space of the boiler, while itsother end is open into the flue, and thence through such iiue into thechimney. On opening the cock in this pipe steam will` pass through it,make a partial vacuum around and below the pipe, and in a manner wellknown to engineers generate a current, thus causing a greater iiow ofgases through the superheating apparatus, and consequent] y theapplication of a greater amount of heat to the sieam to be superheated.By opening this cock to a greater or less extent the amount 'of heatapplied for superheating can be regulated.

I do not confine myself to any precise number, form, or arrangement oftubes, nor to any precise points of connection of the ends of thesuperheating-tlues with the boiler, as such connection-s may be in anyconvenient place, so long as one end of the apparatus is connected at ornear the fires and the other farther off; and I do not confine myself toan apparatus in which the steam is heated while passing through thesteam-pipe, as a drum or chamber connected with the steam-space of theboiler might inclose the superheatingtubes; neither do I intend alwaysto pass the gases inside of the tubes while the steam is outside, as thesame result may be attained by using va large superheating-tlue with asteam-pipe or steam-pipes inclosed therein;

but in making' all such changes care must be taken that only a portionof the products of combustion come in Contact With thesupe'rheating-surfaces, and that there be a pipe or passage independentof the usual boiler ilues, tubes, or connections, such pipe or passageacting to withdraw gases from their usual course and return them again,or else discharge them directly into the air; and also that there shallbe in the discharging end of the pipe or passage a steam-jet such as isspecified, so applied thatit shall When in use increase to a greater orless extent the draft through the passage, and consequently determinethe amount of heat applied to superheat or dry the steam.

I intend to apply proper valves, self-acting or otherwise, to shut ottany portion of the superheating apparatus that may become leaky, andalso to have a proper handle for altering the' position ot' the cock orstopvalve p.

I claim as of my own invention- A steam-jet, or the equivalent thereof,located substantially in the position and serving the purpose specified,in combination with a su p erh eatin g apparatus which is heated by aportion ofthe gaseous products of com bustion, and is otherwisesubstantially the same as hereinbefore set forth.

In testimony whereof I have hereunto subscribed my naine, in the city ofBoston, this 2d day ot June, A. D. 1858.

-GEORGE A. STONE.

In presence of- N. G. LOMBARD, CHARLEs L. LovERING.

